Liquid conductor heater



May 26, 1936. G, H NELSON 2,042,272

LIQUID CONDUCTOR HEATER Filed July 5, 1952 2 Sheets-Sheet 1 v G. H. NELSON 2,042,272

LIQUID CONDUCTOR HEATER Filed July 5, 1932 2 Sheets-Sheet 2 Patented May 26, 1936 UNITED STATES PATENT OFFICE Hankscraft Company poration of Wisconsin Madison, Wis., a cor- Application July 5, 1932, Serial No. 620,799

8 Claims.

This invention relates to improvements in liquid conductor heaters and particularly to improvements in the electrodes of liquid conductor heaters of the type described and claimed in the United States patents of Marshall W. Hanks No. 1,175,442, dated March 14, 1916, and No. 1,683,070, dated September 4, 1928 and Marshall W. Hanks and Max Mason No. 1,683,071, dated September 4, 1928. The principal object of the invention is to provide a liquid conductor heater having an improved electrode construction which permits the electrodes to be constructed easily and at relatively small cost as compared with the forms of electrodes heretofore used. In the operation of liquid conductor heaters of this type, it has heretofore been the usual practice to employ metal plates or the like spaced apart and connected to the terminals of the circuit so that the current is passed between these plates through the liquid conductor, and these plates have usually been perforated to permit the ready escape of bubbles created by the passage of the current. These electrodes frequently become coated with deposits from the water or the like forming the conducting medium and it is often necessary to remove them from the apparatus at intervals for purposes of cleaning or repair. The present invention greatly reduces the inconvenience and difficulty of cleaning and repairing the electrodes by providing a simplified form of electrode which may be constructed at such small cost that it may be replaced at the necessary intervals without unduly increasing the cost of maintenance of the apparatus andwithout seriously affecting the efficiency of operation as compared with the use of the types of electrodes heretofore employed. An important object of the invention is to provide a self-sustaining electrode unit comprising a pair of electrodes which are spaced apart by an insulating medium having sufficient porosity to become saturated by the liquid conductor so that the current passes directly between the electrodes through the saturated insulation. A further important object of the invention is to provide a self-sustaim'ng electrode device comprising a pair of metal electrodes of wire or ribbon form which are provided with porous insulation and which are twisted together in helical fashion to form a selfsustaining unit which may be immersed in the liquid conductor without any other support than that provided at the points where the conductors are connected to the terminals of the circuit. Another object of the invention is to provide a pair of electrodesof wire or ribbon form having insulation surrounding one or both electrodes in combination with means for maintaining the electrodes in assembled relation. A further object of the invention is to provide an improved method of forming electrodes according to which they are constructed in wire or ribbon form or the like and are then provided with porous insulating coverings which are twisted or woven thereon preliminary to securing the two electrodes together. Other objects relate to various features of construction and arrangement which will appear more fully hereinafter.

The nature of the invention will be understood from the following specification taken with the accompanying drawings, in which several embodiments are illustrated. In the drawings,

Fig. 1 shows a side elevation of one form of the improved electrode constructed according to the present invention with a part thereof illustrated in longitudinal section;

Fig. 2 shows a side elevation of a liquid conductor heater including the improved form of electrode arrangement illustrated in Fig. 1, with a portion of the casing of the device illustrated in longitudinal section;

Fig. 3 shows a vertical section through another form of liquid conductor heater, adapted for heating or cooking purposes, in which the electrodes are constructed according to the present invention;

Fig. 4 shows a top plan view of the liquid condu'ctor heater illustrated in Fig. 3 with the cover thereof removed;

Fig. 5 shows a side elevation of a modified form of electrode construction with a portion thereof removed, illustrated in longitudinal section;

Fig. 6 shows a side elevation of still .another form of electrode construction embodying the present invention with portions thereof illustrated in longitudinal section; and

Fig. 7 shows a side elevation of still another form of construction of electrodes embodying the features of the present invention.

In Fig. l of the drawings there is illustrated a pair of electrodes comprising a pair of metallic conductors In in the form of wires, ribbons, tubes or the like, formed of material adapted to withstand corrosion, electrolysis, or the like, and each provided with surrounding tubular covers ll of porous insulating material, such as asbestos or the like. This insulating covering may be applied by winding or weaving the asbestos around each of the metallic members l 0, after which the twoinsulated members are twisted together in helical fashion to form a self-sustaining unit I2 in which the two conductors are maintained in spaced relation and in the desired form by their twisted relationship with each other. Portions of the metallic members II! are left exposed at one end of the unit as shown at Ill for connection with the terminals of an electric circuit.

In Fig. 2, the form of electrode construction illustrated in Fig. 1 is shown as being applied to a liquid conductor heater l3 adapted for the continuous heating of water or the like which is supplied to the interior of the tubular casing l4 through an inlet l5 and which is continuously discharged in heated condition through the outlet l6. The electrode unit 12 is mounted centrally within the cylindrical casing l4 and the terminals I [1 of the electrodes are brought out through the removable insulating plug ll which forms one end wall of the casing. These terminals l0 are connected by coupling members I8 with electrical conductors l9 leading from a source of electrical current so that when this circuit is closed, the metallic members ID of the electrodes are connected in the circuit and current passes between them through the insulating coverings II which become saturated by the water flowing through the casing and which have sufiicient porosity to permit the escape of the steam bubbles which are formed by the passage of current and the heating of the water. It will be noted that this unit maintains itself in place without any other support than that provided at the end of the casing and that it may be readily removed and replaced by another unit when it becomes worn or defective or excessively coated after long-continued use.

In Figs. 3 and 4 of the drawings, there is illustrated an adaptation of the form of electrode shown in Fig. 1 to a type of liquid conductor heater adapted particularly for heating and cooking operations. In this form, there is provided a vessel 20 formed of porcelain or other insulating material, or the like, and provided with an electrode unit l2 comprising two metallic members I0 having insulating coverings II and twisted together in helical fashion so that they are maintained in the proper spaced relation. This twisted helix is itself bent bodily into substantially circular form, as shown in Fig. 4, so that it occupies the circular depression 2% formed in the bottom of the vessel 20. The terminals In of the metallic members of the electrodes are connected to terminal posts 22 which pass downwardly through the bottom wall of the vessel and are connected to the conductors 23 leading from a source of electrical current supply. These conductors 23, which are insulated except at their terminals, are coiled about the terminal post 23 and are clamped in place by nuts 24. The vessel 20 has a downwardly and outwardly flared annular flange 20* which is adapted to rest upon a table or other support and it has an upwardly and outwardly flared annular wall 21'] which surrounds the space 25 in which the liquid conductor is located and in which, or above which, the heating or cooking operations take place. The vessel 20 is provided about its upper edge with an upwardly extending rib 20 surrounding an annular shoulder 20 upon which the dome-shaped cover 26 rests. This cover is provided with a handle 26 which may have an inner chamber with a small passage leading therefrom to the space beneath the cover so that the liquid conductor may be gradually supplied to the electrodes at the commencement of the operation of the apparatus,

as explained in the prior patents above referred to.

In Fig. 5, there is illustrated still another method of constructing the electrodes according towhich the two metallic electrode members 30 are provided with insulating coverings 3| wound or woven thereon with terminal portions 30 of the metallic members exposed for connection in an electric circuit. Instead of twisting these insulated members together, they are laid side by side in parallel relation and are bound together by a surrounding flexible member 32 which may be of either conducting or non-conducting material. In case this member is formed of conducting material, it may act as an intermediate electrode to which current passes from one of the conductors 30 and from which current passes to the other electrode 30. It will be apparent that the form of construction shown in Fig. 5 may be embodied in liquid conductor heaters of the types shown in Figs. 2 and 3.

In Fig. 6 of the drawings, there is illustrated still another form of electrode construction in which two metal electrode members 35 are provided with tubular insulating coverings 36 which terminate short of the ends of the members 35 so that the portions 35 are exposed for connection with the terminals of an electric circuit. These two insulated members 35 are placed parallel to each other within a, surrounding metallic shell 31 which holds them in assembled relation and which is preferably provided with a plurality of perforations 31 distributed over its surface,

so that the escape of bubbles created by the pas-- sage of current through the saturated insulating material is readily permitted while at the same time the liquid conductor is allowed free access to the insulating coverings of the wires so that a circuit is readily established between the conductors 35 when these conductors are connected in a circuit and the electrode unit including the shell 31 is immersed in a liquid conductor.

In Fig. '7, there is illustrated a simplified form of electrode construction in which a metallic conductor 40 of wire or ribbon form or the like is surrourfded with an insulating covering 4| having wound thereon another metallic conductor 42 which is coiled about the insulated conductor 40 in helical fashion so that the two conductors are maintained in assembled relation and in definite spaced relation. The terminals W and 42 of these conductors which serve as the electrodes, are adapted to be connected in an electric circuit and the construction is capable of being em bodied in various forms of liquid conductor including those illustrated in Figs. 2 and 3. In any of these forms, the electrodes may be readily removed and replace-d and it will be apparent that the electrodes themselves may be constructed at relatively small cost. Due to the form and arrangement of the electrodes, the escape of steam bubbles is readily permitted through the pores of the insulating material.

Although several forms of the invention have been shown and described by way of illustration, it will be understood that it may be constructed in various other embodiments coming within the scope of the appended claims.

I claim:

1. The combination in a liquid conductor heater, of a vessel adapted to contain a liquid conductor, and a pair of self-sustaining electrodes each having one end mounted in the wall of said vessel and projecting endwise into said vessel and resting on the lower Wall thereof, one of said electrodes being provided with a tubular cover of insulating material.

2. The combination in a liquid conductor heater, of a vessel adapted to contain a liquid conductor, and a pair of self-sustaining electrodes each having one end mounted in the wall of said vessel and projecting endwise into said vessel, one of said electrodes being provided with a tubular cover of insulating material, said electrodes being twisted together in helical fashion and spaced apart only by the insulating material thereon.

3. The combination in a liquid conductor heater, of a vessel adapted to contain a liquid conductor, and a pair of electrodes mounted in said vessel and each having one end thereof mounted in a wall of said vessel, said electrodes resting on the lower wall of said vessel, said electrodes being spaced apart by tubular coverings of insulating material and being twisted together in helical fashion.

4. The combination in a liquid conductor heater, of a vessel adapted to contain a liquid conductor, a pair of electrodes provided with porous insulating coverings and twisted together in helical fashion within said vessel, and a pair of terminals each mounted in a wall of said vessel and connected to one of said electrodes,

said electrodes being arranged to rest on the lower wall of said vessel and to be spaced therefrom by said insulating coverings.

5. The combination in a liquid conductor heater, of a vessel adapted to contain a liquid conductor, and a pair of electrodes mounted in said vessel, one of said electrodes being provided with a porous insulating covering, one of said electrodes being twisted in helical fashion around the other electrode.

6. The combination in a liquid conductor heater, of a vessel adapted to contain a liquid conductor, a pair of electrodes mounted in said vessel and spaced apart by porous insulated coverings, and a metallic member surrounding said electrodes and having means for permitting said liquid conductor to pass therethrough.

7. The. combination in apparatus of the class described, of a pair of self-sustaining electrodes twisted together and spaced apart by a porous insulating covering.

8. The combination in apparatus of the class described, of a pair of self-sustaining electrodes in the form of conductors twisted together and spaced apart by porous tubular insulating coverings.

GEORGE H. NELSON. 

